Fuel cell assemblies convert a fuel and an oxidant to electricity. One type of fuel cell power system employs use of a proton exchange membrane (hereinafter “PEM”) to catalytically facilitate reaction of fuels (such as hydrogen) and oxidants (such as air or oxygen) to generate electricity. The PEM is a solid polymer electrolyte membrane that facilitates transfer of protons from an anode to a cathode in each individual fuel cell normally deployed in a fuel cell power system.
In a typical fuel cell assembly (stack) within a fuel cell power system, individual fuel cell plates include channels through which various reactants and cooling fluids flow. Fuel cell plates are typically designed with serpentine flow channels. Serpentine flow channels are desirable as they effectively distribute reactants over the active area of an operating fuel cell, thereby maximizing performance and stability. In subzero temperatures, water vapor in the fuel cell assembly may condense. Further, the condensate may form ice in the fuel cell assembly. The presence of condensate and ice may affect the performance of the fuel cell assembly and may also cause damage to the fuel cell assembly.
During typical operation of the fuel cell assembly in subzero temperatures, waste heat from the fuel cell reaction heats the assembly and militates against vapor condensation and ice formation in the assembly. However during a starting operation or low power operation of the fuel cell assembly in subzero temperatures, water vapor may condense and the condensate may form ice within the fuel cell assembly.
It would be desirable to develop an apparatus and method for quickly and efficiently heating the fuel cell assembly during the starting operation to militate against vapor condensation and ice formation in the fuel cell assembly.